Conquest of the Lich King
by Lord22
Summary: Arthas Menethil has ascended to become the Lich King. But the scourge is broken and ruined and the Forsaken and Alliance are pressing their advantage. In a desperate fight to maintain his holdings, Arthas finds himself battling once more to save his people and his soul...
1. The Ascension

**Chapter One: The Ascension**

The battle was over. The Blood Elves and Naga were repulsed and Anub'arak was holding the line against any resurgence. In a final, desperate bout, Illidan had confronted Arthas directly. It had been the hardest battle he'd ever fight, but in the end, Arthas had been victorious.

And yet as he looked at the wounded Demon Hunter, Arthas found he could not bring himself to slay him. Illidan was an exile from his people for doing what had to be done. He'd been betrayed for taking actions that the Druids had failed to do.

He was a hero, scorned by all.

It was something Arthas had though himself to be once. And so he turned away and left him there to live or die as he chose. Turning to the Icecrown Glacier, he'd begun to scale it. He passed through the icy gates and felt a chill blacker and more terrible than any he'd experienced. Every step was heavier than the last, though a voice urged him on.

As Arthas walked upward, he heard the voices of old friends around him. Muradin, Uther, Jaina, their accusations echoing in his ears as he went ever higher.

_"You lied to your men, and betrayed the mercenaries that fought for you!"_

_"Have you lost your mind, Arthas!"_

_"I'm sorry Arthas, I can't watch you do this."_

He shrugged them off. Their condemnations were irrelevant, for he could not leave without reaching this point. Up and up Arthas went until he came before what he had served with faith and loyally he had never felt. A spirit that had been beside him, driving him onward to destroy his enemies. He'd resisted it often, but now he remembered how it had driven him against Sylvanas.

To bend her to his will, to crush her forces. After a campaign of restrained humiliation, it had been satisfying to defeat them. And yet it had resisted when he slaughtered the Blackrock Orcs. How it had torn at him as he wiped out every man woman and child.

Now here was the god so many gave their souls for.

The skeleton of an orc trapped in ice. Or was it a ghost of a skeleton trapped within armor. Yes, there was no true bone there.

"Return the blade…" said the voice of the Lich King. "Complete the circle. Release me from this prison…"

The voices reached a crescendo as Arthas drew back his sword and struck. The blade shattered the ice and the armor fell away. Around Arthas, the glacier began to crack and break. It collapsed around him like a waterfall of snow. The helm fell before him and Arthas was driven to reach down and take it.

Drawing it up, he placed the helm on his head. And Arthas saw blue light as he beheld the world around him.

Then, he was standing within a great hall. Before him were two figures. One was immensely powerful, an orc clad in furs. Yet he was but the face of a far greater being, something Arthas could see only hints of. The other was a boy, sick and starving, but held on by a grim determination. Small mercies had fed him, driving him to draw on still more mercies. Though Sylvanas had been a heavy blow.

"He is gone already." Said the orc.

"You do not have him yet.' Said the boy, giving the orc cold look. A look of furious defiance, born in endless hatred.

"I'm sorry, who are you?" asked Arthas, annoyed at mysteries. "And what is this place?"

The orc looked at him with an expression that told Arthas he knew full well who he was. He was the Lich King, Ner'zhul, incarnated here as he once was. "This place is a domain of spirits. The place where the power of the Lich King resides in full. We are each of us aspects of the Lich King."

"Hardly." Scoffed Arthas. "I've no interest in being a god." He'd no interest in anything.

"It is that trait that led me to choose you, Arthas." Said the orc. "You serve others without regard to yourself. It is why you were known as the best of the paladins. It is why the scourge triumphed over the Legion.

"Together, we have engineered the death of Archimonde and laid low the armies of the Legion.

But we have much work left to do."

"I'm well aware." Said Arthas. "Kael'thas left quite a trail of destruction behind him. If I hadn't arrived when I did, you'd be shards of ice.

"Who is this boy then?"

The orc looked to the boy, who glared back with silent fury. "This is a phantom."

"I am more than that." Said the boy. "I am who you once were. I am your memories of Jaina, your love for your people-"

"I have no time for this." Scoffed Arthas.

But the boy held his gaze. And Arthas found he could not now look away from it. "You don't have to continue like this. You can return to what you once were?"

"Really?" asked Arthas. "And how do you suggest I do that?" He wanted to know the answer, even past his sarcasm.

But the boy was silent.

"I'm waiting." Said Arthas.

"You could repent and throw yourself at the mercy of the paladins." Said the boy, with the air of one who has not considered the question before.

Arthas scoffed bitterly. The paladins had never attempted to free or dissuade me. They'd jumped at the chance to make their self-righteous speeches. "And they would immediately kill me. Judging from my record of kills at this point, I don't imagine the light would be in a forgiving mood."

"Uther taught us that the light could forgive anything." Said the boy.

Arthas doubted it. But even if it was true, it did not matter. "In that case, we might as well ask its pardon while still alive. I see no reason to submit myself to self-righteous priests.

"If they wanted me redeemed they would have tried to redeem me."

His other self was grasping at straws now. "You could go to Jaina, ask her-"

Arthas laughed now, feeling the scorn more than ever. "Jaina is a fool. She abandoned me to go follow the wishes of that rambling madman."

"He was right." Noted the boy matter of factly. "Your lust for vengeance drove your people into his hands."

"Did it?" asked Ner'zhul. "I seem to remember the Alliance turning on you long before that. Uther forced you to trap your men here. If he had swallowed his pride and helped you purge Stratholme we would not have ever come to this point."

"And what of Muradin?" asked the boy. "You left him to die in the snows so you could claim that blade. When did he betray you? What of your men who struggle to survive in Northrend even now? Falric, Marwynn, how did they betray you?"

Where once Arthas was forced to hold the boys gaze, now he could hardly meet it. His thoughts searched over the sight of Muradin recoiling. "…It hardly matters.

"Even if I wanted to return to that life I cannot. The Alliance would simply kill me. If I wished to make amends it would be useless to submit to them.

"As for Jaina, do you really think she'd take me back? And do you really think she has the power to withhold me from the Alliance? Or the desire?

"No, any reunion would be of the tears shed from the other side of the cell variety.

"I think not." He had no intention of dying for the sake of redemption. "Anything else?"

The boy flinched at this. The possibilities were fading away, destroyed by cold logic. One could not do the things they had done and simply walk away. "You could become a wandering warrior, shed the name of Arthas and fight the legion."

"In that case, I might as well become Lich King and use armies of undead to fight the legion far more effectively." Noted Arthas, though it was a good idea. "Do you have any other suggestions? Any that could not be performed better with the use of an undead army?"

"…You could allow the Blood Elves and Naga to flee this land and escape back to their own domains. There isn't any point in killing more of them." Said the boy. "They are a broken people."

It was a start. Arthas smiled. Now we're finally getting to practical solutions. Ones' with no need for you." Then he drew his sword and place it to the throat of the spirit. "Begone, spirit. And take your due place."

The boy did not flinch. He held Arthas' gaze even as he faded. "You will remember me before the end."

Then he was gone. Arthas considered how many of the prophecies with good results had come true. Then he scoffed again. "I doubt it."

The boy was gone. Not dead. But brought into the fold. The desires he represented were not possible. His hopes and dreams were shattered beyond repair. But the aspects which drove those hopes and dreams were now within Arthas.

He felt strong. Stronger than ever now.

Ner'zhul blinked in surprise. "That took significantly less time than I expected."

Arthas looked to him with newfound contempt. 'It isn't the sort of decision that requires half a decade of sleep to come to. Now, as long as we're here, logically I should kill you and become Lich King in my own right."

Ner'zhul stood and clenched a fist. "You won't find it easy. I am a god in my own right. This… orc is but a shell of flesh."

"Perhaps, but I doubt you're any more terrifying than the spawn of that Forgotten One." Noted Arthas. "Can you give me a reason not to kill you?"

"Do you have an actual reason for wanting me dead?" asked Ner'zhul.

The emotions were coming to Arthas, but they were muted and restrained. He'd never been one for self-righteous speeches and any he made would be… hypocritical, to say the least. "You had me obliterate the nation I was one day going to rule. Granted, I feel nothing for all those who've I've slaughtered within. But I still hold resentment at being forced to destroy something that is mine.

"I also have no special love for you. It's also against my job description to not murder someone I have no use for at this stage."

Ner'zhul smiled as power radiated from him. Arthas glowed with a pale light that met the Lich King's blackness. The auras clashed there, driving against one another with neither the stronger. "Amusing.

"Perhaps I should clarify my motives before we go any further with this confrontation."

Arthas drew back his will, as Ner'zhul did the same. "You mean your inexplicable desire to destroy all life?"

Ner'zhul cackled aloud. "You give me too much credit, Arthas. The truth is that I've had very selfish and petty motives from the very beginning. I have no grand vision for a paradise of eternal darkness, as Kel'thuzad put it.

"My goals have been twofold: First, to secure independence from the Legion. To do so, I had to remove Archimonde and ruin his invasion. And then establish a powerful stronghold to prevent further incursions. That has been achieved by our cooperation.

"Second, to achieve a new physical form. Icecrown was designed to fail eventually.

"I also had a secondary goal of ensuring the survival of my species with the invasion of the Legion. Thus why the orcs never had to contend with any undead forces they didn't deliberately engage."

"What about the Blackrock Clan?" asked Arthas. "I killed every man, woman, and child in that place."

Ner'zhul narrowed his eyes. "Just as you seek to avoid slaughtering the human and elven populace when it could be avoided. I suppose you consider yourself avenged in that regard.

"At present, the score between us does not matter. The Scourge is shattered and broken. Illidan's assault has only barely been repulsed. Kel'thuzad is reforming our loyalists at Stratholme as we speak. The Banshee Queen, Sylvanas, is consolidating her forces. The humans are organizing into a new order as we speak. The Scourge will be hard-pressed soon."

"I missed the part where that is my concern." Said Arthas, tempted to walk away just to spite him.

"Well, it is your kingdom." Said Ner'zhul. "I would hate to see you lose another. If you killed me now, you would become the Lich King. But you would not understand how to coordinate the Scourge en masse. And when acting in a strategic capacity you would be unable to command from the front as you prefer."

"So, an alliance." Said Arthas. He could not, in good conscience, abandon Kel'thuzad and those who served him loyalty. Many had sacrificed themselves for his sake, after all."

"Yes." Said Ner'zhul. "I will inhabit your form and take you as a… protégé. Our wills will cooperate to rebuild our holdings and deal with the Legion. I'll have a competent general who is, as of yet, undefeated In the field of battle. Something I will need. In return, I will oversee the gradual reconstruction of the scourge. I will provide you with the armies you will need.

"Eventually one of us will betray and destroy the other."

"I see." Said Arthas. "So only together may we reconstruct the Scourge from the ashes and build an army unlike any other. You'll forgive me if I find it less than inspiring."

"I am perfectly willing to consult you on matters of foreign policy for now." Said Ner'zhul. "But the fact remains, we stand together in this, or not at all."

Arthas considered his options and found them shockingly limited. If he were to establish a place for himself, he would need an army. Finally, he relented and sheathed his sword. "…Very well, Lich King. We'll play your game."

"Then give me your hand in pledge." Said Ner'zhul, offering it.

Arthas took the hand.

The blue energy faded and Arthas opened his eyes to perceive the endless flows of fate and mana. His gaze fell over the landscape, blinking beneath the daylight. He could perceive everything, understand aspects of things he'd never considered. He no longer saw rivers of freezing water, but endless tiny particles called water.

_**"Now we are one."**_

It was a lie. But one spoken from both minds for the moment.

* * *

**Author's Note:**

Okay, a bit of context.

This was my original ending for the Mercyverse. Before I decided to have Arthas not go after Sylvanas. When he did that, it set off a row of dominoes that threw things off the rails.

In my original plan Arthas would ascend the Frozen Throne but as a noble demon of sorts.

Since a bunch of people requested I rewrite Wrath of the Lich King, this is the beginnings of my attempt.


	2. Defense of Stratholme

**Chapter Two: Defense of Stratholme**

Arthas made his way down the steps of the spire and onto the corpse-strewn battlefield. The snows here were shed with fresh blood, and the stink of corpses was everywhere. And yet it was oddly silent, with the only sound being the wind whistling over frozen tundra. This place was not the home of any living thing, the Ice Trolls who once dwelled here had long since fled.

It was Icecrown, and the only thing that dwelled here were ghosts. Arthas would be glad to get out of this place as quickly as possible. He could see why the Legion had chosen to put the Lich King here. Nobody would want to live in a place like this, so his arrival might be unmarked by the world at large. Down he went and came at last to Anub'arak.

Anub'arak was a giant combination of spider and beetle. His body was covered in a massive violet carapace, and where he walked, the ground shook. His spikes were covered in the blood and entrails of their enemies. Now he seemed to be sending forth small insects to feast on the corpses of dead warriors.

As they did, the beetles grew larger and larger. Soon they began to tear at each other, devouring one another. Finally, only one beetle remained, nearly as tall as a human and longer than a dog. Its mandibles clicked at it, gazed at him. Once, it would have unnerved Arthas.

Now, however, he'd been saved by these creatures many times in Azjol Nerub.

The great Crypt Lord turned around to where Arthas stood, noticing him at last. There was a long silence as he noticed the helm. "You return, Death Knight." His voice was as hollow as the crypts he stayed within.

"Lich King now." Said Arthas. "I am pleased to see you still alive, Anub'arak."

"It was a narrow thing." Said Anub'arak. "But, the wounds will mend." He paused. "That helm… You have ascended. Did you kill Ner'zhul?"

"No," said Arthas, feeling a bit disappointed about the fact.

"A pity." Said Anub'arak, sounding annoyed. "No matter, the Blood Elves, and Naga have fled back from whence they came. They took their wounded leader with them. The day is ours."

"For what little it is worth, I suppose it is." Said Arthas, before curiosity took him. "Anub'arak."

"Yes?" asked the creature.

"What was that thing that we faced in the tunnels of Azjol Nerub?" asked Arthas.

"An ancient creature spoken of only in our oldest histories." Said Anub'arak. "A forgotten one, the spawn of Yogg Saron."

"Yogg Saron?" asked Arthas. He'd read that name in some of the old histories of Lordaeron.

"The God of Death, a primal force long ago imprisoned within these lands by the titans." Said Anub'arak.

Arthas nodded before looking up to where a black-haired female cultist was giving orders. She and her subordinates were busy summoning up fortifications around the glacier. He looked to Anub'arak. "We can discuss this later. What are they doing?"

"Fortifying this area." Said Anub'arak. "A precaution, I felt worthwhile."

"It was a wise one." Said Arthas. Sheathing Frostmourne, he made his way over to the cultist, and she turned to him and bowed. "Serena."

"Yes, King Arthas?" asked the woman.

"I want you to continue reestablishing the fortifications we lost here." Said Arthas. "Don't launch any offensives, but be sure to guard against future assaults. You are in charge of reestablishing Icecrown as our capital." He turned back to where Anub'arak was scuttling with remarkable speed toward them. He loomed very high. "Anub'arak, take our forces and guard the passes.

"I doubt the living denizens of Northrend will simply sit back while we lie here weakened."

"What will you do?" asked Anub'arak, hollow voice having a slight note of concern.

"I have a meeting to attend to with Kel'thuzad." Said Arthas, taking hold of Frostmourne in an undergrip. "Lordaeron has been a blind spot in our calculations for far too long."

"Good luck." Said Anub'arak.

"At what point have we ever had good luck?" asked Arthas with a grin.

Then he unsheathed Frostmourne. Raising his sword, he brought to mind spells of teleportation Ner'zhul had learned long ago. Transporting himself far away, he stood once more in Stratholme. The houses stood now as bastions of undead who stalked the broken streets. The gates were shut tight, but flames were kicking up in the houses around them.

Great stones were being cast over the walls to crash beyond. They landed to shatter houses to pieces. Others smashed against the masonry of the walls and gatehouse. Snarls and cries of war could be heard all around him, as undead scurried with water to put out fires. It was all very organized and meticulous, even with a small amount of undead.

The bulk of the army seemed focused on the walls themselves. And justly so, given the vast numbers of undead clad in red moving forward. They were many, with abominations and ghouls and crypt fiends in vast numbers. Arthas sensed for the most loyal of his subjects and went to them. Kel'thuzad stood on the battlements, casting down waves of ice upon the coming swaths. The Lich looked on calmly as the advance continued. Arthas expected he could have held here, even without him. But they would do more than hold.

Waves of black-feathered arrows were launched into the coming ranks. Many of them found their mark, and the enemy died in droves. Enemy archers returned in kind, only to clatter off the battlements. Drawing Frostmourne, Arthas raised it high, and a great cry went through the defenders. They took heart.

"King Arthas, you return." Said Kel'thuzad, floating around, his chained arms crossing together. He looked pleased at his presence.

"Yes, I have Lich." Said Arthas, glad to see the Lich alive. Even if he'd known he was alive from Ner'zhul's thoughts, it was good to see it confirmed. "I need you to give me an immediate briefing on everything that has happened up until now."

"Would you prefer to do that before or after we drive off the army at our gates?" asked Kel'thuzad, tone droll.

The enemy reached the walls. They splashed through stagnant waters. A withering rain of projectiles to set ladders against the wall. Soon they were raised upward one by one, hooks clinging to the fortifications. Ghouls and skeleton surged up like rats. They were quite determined.

Arthas raised Frostmourne and realized they were outnumbered. So much, the better. "After would be good."

Then he threw aside his cloak and rushed into the fray. Even as the waves of undead clambered over the walls, he was upon them, hacking and slashing through them in a blur. Where he walked, the enemy died, and the defenders fought with still greater strength. Flames of darkness descended and burned the enemy, as the undead ripped each other to shreds.

"Forward my subjects!" cried Arthas as he shoved a ladder downward with one hand. "Drive the enemy before from the walls! Let not one survive!"

Then he looked to the gates. Even now, there was a great ram approaching them. He readied himself to spring down upon it and kill the crew. Yet another way presented itself, for he had far greater power now. A smile came to his face as the power of Ner'zhul flowed through Frostmourne.

It was a wave of darkness that shot down toward the ram. It struck it head-on, and it burned, blasting to cinders at the moment. The darkness then rippled outward, killing all around it and crushing the advance. Around him, the assault faltered. The enemy looked up to the walls, doubt clouding their mind as the battle turned against them.

"The Lich King is with us!" cried a necromancer as he raised more undead. "Fight on brethren! The traitors shall not take Stratholme!" Waves of corpses rose again to fight their former masters. Everywhere the taxed defenders were bolstered.

Arthas called aloud to his warriors, cutting down all who stood before him. Not one could lay a hand on him as he slaughtered them. Wherever he went on the walls the enemy soon recoiled and fled. Frostmourne's hunger was, for once, satiated by the never-ending flow of life forces.

And yet still it went on.

On the battle went, and across the wall, the enemy drew back in fear. At last, they fled, scaling back down the ladders or hurling themselves from the walls. But they did not know what to fear. It had not yet dawned on them who they faced. Only a pale rumor of the truth reached them. Even now, Arthas could perceive the enemy commander, Varimathras.

The Dreadlord guessed that some champion had come from Northrend to aid the defense. It was true. But he did not guess at his full peril. Arthas would demonstrate it to him in due time. For now

Arthas met Kel'thuzad at the gatehouse, and the Lich bowed. "They've drawn back their hand to their outer fortifications, my king."

Arthas nodded. "Well done. Raise the bodies and repair these defenses at once."

"You seem to have more than recovered, my King." Said Kel'thuzad.

He had been sick months ago. No more. Arthas spun Frostmourne round twice and sheathed it in one smooth movement. "Your talent for stating the obvious remains unmarred by defeat, Lich. Who are these undead? I noted Varimathras as their leader?"

"Do you not already know?" asked Kel'thuzad, sounding surprised.

Ner'zhul did, of course, and offered the information. But Arthas did not want to mix his mind with the orc any more than necessary. So he ignored it. "I am of two minds on the subject. Tell me now."

"The Dreadlords are defeated." Said Kel'thuzad. "What remains of their forces now serves the Banshee Queen, Sylvanas. Or the Dark Lady as she calls herself.

"Varimathras defected over to Sylvanas, Balnazzar and Detheroc are, as far as I know, dead. As of this moment, Sylvanas controls a large part of the Scourge, and this army was an advance force."

"How did Sylvanas manage to defeat Balnazzar?" asked Arthas, not surprised. "She can't have had much support?"

"She utilized alliances with local creatures to defeat Varimathras." Said Kel'thuzad. "With his information, she destroyed Detheroc. From there, she made an alliance with Grand Marshall Garithos and destroyed Balnazzar.

"That was when she made her first mistake."

"What was it?" asked Arthas.

"She murdered Grand Marshall Garithos in cold blood, during a parley." Said Kel'thuzad, sounding distasteful at the prospect. Murder during parley? Arthas wasn't aware Sylvanas had sunk that low. "Many of her supporters were, nominally, on the side of the Alliance. They viewed their crusade as throwing off their evil masters. The act caused many of them to lose faith in her.

"Eventually, she won some back over by letting his armies leave. She mollified them with tales of how the Alliance tried to murder Prince Kael'thas. But the time she spent negotiating gave me time to shore up support in Stratholme. It also gained more than my share of converts."

"Converts?" asked Arthas. "Why should those who favor the Alliance support me?"

"There are those in her armies who regard you as preferable to her, even if they hate you both," said Kel'thuzad. "You never killed anyone in parley and left most of the Alliance intact.

"Whatever the case, we now control only the area around Stratholme. As we speak, Sylvanas is consolidating her hold on this region."

"Then I will prove my power, once again." Said Arthas. "Ready the warriors for an assault. We're going to break this siege."

"Are you certain, King Arthas?" asked Kel'thuzad, voice curious. "The Alliance is remobilizing. Many of those who worked for Garithos has been absorbed into a new force, the Scarlet Crusade."

"Who leads them?" asked Arthas.

"A paladin named Alexandros Mograine." Said Kel'thuzad. "I believe he has some sort of magic sword of some description. Whatever the case, if we draw the conflict out, Sylvanas will eventually be forced to withdraw."

"Perhaps." Mused Arthas. "But it would leave her the stronger power." He looked to where the attackers had fled to. Varimathras had constructed a great wall of black stone around Stratholme. No doubt to prevent any attempt to sally forth. Clever of him, though the wall paled in size to his own defenses. "This wall, have you detected any weaknesses in it?"

"We have not had time." Said Kel'thuzad. "Our focus has been wholly on driving off the attacks."

"It must be broken if we are to secure the plaguelands." Said Arthas. Then he focused through his helm and sent forth his will. Her surveyed the entire wall and noticed one part of it that was cracked. It had been built on unstable foundations and even now was sinking inward.

Of course, he might be able to unleash his power full on. But doing so would unveil him too early. If everyone knew that the Lich King had returned stronger than ever, they would unify. That had been the Legion's downfall. Better to keep a low profile until he had reorganized his forces. And while everyone thought his forces were in chaos, they would fall on each other like wolves in winter.

One of the most enduring qualities of the living was their willingness to eat their own, after all. Still, once Arthas had secured his holdings, what would he do next? His subjects would look to him for some grand design, but he had none in mind. Perhaps Ner'zhul had some conception of what to do next, but Arthas would not serve him forever.

He turned his mind from the future. It didn't matter. Survival was the first thing to be concerned about.

"The leftmost part of their walls is weak." Said Arthas. "I'll lead an assault there myself. Kel'thuzad, I want you to send out some cultists to begin summoning ziggurats outside the gates. Have the meatwagons and abominations defend the advance.

"I want you to make the appearance of a gradual advance toward the front. When you finish one spirit tower, build another one a little closer. If they attack, drive them off."

"That plan does not seem workable." Said Kel'thuzad.

"It does not need to be workable. I merely want to make enough noise, so Varimathras focuses his mind on what I'm doing with the spirit towers." Said Arthas. "The real strike will come elsewhere."

Kel'thuzad nodded. "…As you command."

Arthas had been driven out of most of Lordaeron. But he meant to reclaim his kingdom soon enough. It would begin with his counterattack…


End file.
